On the sidewalk outside Arlene’s Grocery, a dive bar and cramped concert venue on New York City’s famous Lower East Side, a gaggle of reporters replaced the huddle of banished smokers and texting hipsters that usually gathers outside such establishments.

Joining them were women. Lots and lots of women.

The unusual congregation had gathered to gawk at a group of female Hasidic alt-rockers, the Bulletproof Stockings, who were making their Manhattan debut. Their religion wasn’t the only point of fascination, as the concert came with a rather unorthodox admission policy. Only women could watch the band perform.

According to a Jewish law called kol isha, literally meaning “voice of a woman”, men cannot hear women sing live, as it risks inciting impure thoughts. So how could this clearly ambitious band – a film crew for the upcoming Oxygen series Living Different documented every moment – play the kind of gigs needed to drum up the necessary buzz?

The solution was simple: ban men from their concerts so they could sing freely or, as Jezebel put it in a laudatory post, nix the “mixed-junk crowd”. With that decision, Bulletproof Stockings not only adhered to Jewish law, but created a novelty factor that drew attention without resorting to the usual pop-star playbook of outrageous costumes and club brawls.

The band’s frontwomen, Perl Wolfe (vocals and keyboard) and Dalia Shusterman (drums) were nonetheless careful to emphasise that their signature request was not about restriction. “This is pro-women, not anti-men,” said Wolfe.

“It’s not about limitation. We choose to make a space [for women] to listen, and it’s up to the man not to listen,” Shusterman added, pointing out that kol isha puts the burden on the man to turn his ears from temptation. “Feminist women are getting it.”

All of Wolfe and Shusterman’s shows have been exclusively for women. They usually perform at smaller venues in Brooklyn – “flower shops and galleries,” Wolfe said – sometimes with other all-female acts.

The two grew close as roommates. Shusterman, 40, is a widow with four children who works in graphic design; Wolfe is a 27-year-old divorcee who up until recently worked as a makeup artist. After deciding to pursue their joint passion for music, they worked out their schedules to allow themselves to practise extensively.

It took some convincing to get Arlene’s to book them. The pair had to launch a petition and gather signatures to prove they would be able to sell tickets. On Thursday night, the concert space was packed from wall to wall.

“We chalk it up to the Man Upstairs,” they joked.

“The guys aren’t liking it. They just really want to hear us live, and it’s getting to them,” Wolfe gloated as the band – expanded for the night to include a violinist, guitarist and cellist – took the stage shortly after 8pm. (Don’t worry, gents: you can listen to their music here.)

Bulletproof Stockings, as the name suggests, dress in compliance with Jewish custom: covered elbows, covered collarbones, covered hair for the married women. Their sound, however, is anything but reserved.

While they have yet to really nail down their musical identity, there is a bite of Fiona Apple, courtesy of Wolfe’s raspy, and sensual, vocals. Their set features a variety of styles: country for Vagabond’s Wagon and pop for Frigid City, which got the women wiggling their hips to the music, the fabric of their long skirts billowing in time with Shusterman’s bold drums. The influence of Jewish music was evident in Sapphire Rains, and at one point Wolfe performed a traditional Hasidic nigun, a Hebrew tune sung communally that features repetitive sounds, a cappella. A few Orthodox women joined in.

Although the audience was limited to one gender, those who showed up provided an incredibly diverse sight: there were women with shiny wigs and women with short hair and stud earrings. There were old women, young women, devout women and agnostic women. There were women who spoke English and women who chattered in Russian; women with afros, women with jewfros. There were women in sheitels, taking selfies.

Most of the attendees found the lack of male presence liberating, even empowering.

“I don’t mind women being separate and wanting to have their own space sometimes,” said Alexandria Kasden, a 28-year-old marketing director who grew up and still lives in Crown Heights. Kasden, who is not religious but has Hasidic relatives on her father’s side, said the Bulletproof Stockings gig was one of the “most chill, unself-concious” she had ever attended.

Several concertgoers mentioned that their male friends had demanded reports after the show.

“It elevates the music somehow,” Chriss Williams said, of the no-boys-allowed policy. “It’s like women’s night out. You don’t have to worry about hitting on guys. It puts the attention on the music.”

Others believed the band could help shatter some stereotypes about Orthodox Jewish women, and the Hasidic community in particular. “People think we don’t get to have fun and we’re stuck in a bubble,” said Feigy, a woman from Hasidic Brooklyn and a relative of one of the band members.

After conquering the Lower East Side – and perhaps the media’s imagination – the Bulletproof Stockings hope to garner a global audience, even if their live ones are only female.

“[In Judaism] Women are supposed to be leaders, to spread light and positivity,” said Wolfe. She and Schusterman hope their success inspires “more and more religious women to come out of the woodwork and show their talent”.